Scaring also reminded jurors they could find Borukhova innocent, even if they believe her co-defendant to be guilty.

Mallayev's fingerprints were found on the makeshift silencer at the scene. A witness testified she watched him pump two rounds into the doomed dentist.

"If you do find that [Mallayev] did this, that's not a basis to find she did this. You don't know what his reasons were. You don't have the evidence to connect him to Dr. Borukhova," Scaring said.

Mallayev's lawyer Michael Siff defended the accused triggerman, who did not testify.

Siff dismissed the fingerprint evidence as "junk" science, "smoke and mirrors, opinion and conjecture at its worst."

He also said it was "impossible" for the prosecution's central witness to have so clearly seen Mallayev shoot the doomed dentist, and suggested her identification was tainted by media coverage of the case.